Los Angeles Dodgers starting pitcher Clayton Kershaw works out in the infield prior to a Major League Baseball game against the San Francisco Giants at Dodger Stadium on Saturday, June 16, 2018 in Los Angeles. (Photo by Keith Birmingham, Pasadena Star-News/SCNG)

LOS ANGELES — Clayton Kershaw’s return to the mound remained uncertain Saturday. No one could say with any degree of certainty when he would be sound enough to make his first start since going on the disabled list June 1 with a strained lower back. Manager Dave Roberts didn’t venture a guess.

Roberts did outline what the next steps would be for Kershaw, with a simulated game scheduled for either Tuesday or Wednesday at Dodger Stadium, while the team is on the road playing the Cubs in Chicago. Kershaw could throw as many as four innings.

“If it goes well, there’s a bullpen (scheduled) for a couple of days after that, then a rehab assignment somewhere, and then we’ll go from there,” Roberts said before the Dodgers faced the San Francisco Giants in the second game of their three-game series.

Kershaw was sidelined Saturday for the 13th game because of his back ailment. He also sat out for 21 games in May because of tendinitis in his biceps. He has made only eight starts in 2018 because of the injuries, including only two since May 1.

Roberts acknowledged the need for erring on the side of caution as the Dodgers work slowly to return the left-hander to their rotation. His lack of starts has played a role in their desire to take a slow but steady approach to his rehab and recovery.

Kershaw’s absence seemed to signal serious trouble for the Dodgers in May, but then they went 11-10 without him while he was on the DL with the biceps injury. They have sizzled without him in June, going 10-2 going into Saturday’s game against the Giants.

“We have to build him up to get him to pitch, sync his delivery up, all that stuff, so we don’t have to revisit this again,” Roberts said. “We’ve taken the time right now to get him to where he needs to be so he feels confident, comfortable going forward. That’s really important.”

Additionally, Kershaw has focused his recovery on mechanics, something new for him.

“I think with Clayton, it’s adjusting to a new normal,” Roberts said. “You look at what he’s gone through the last few years physically. To go through that, that’s one variable that’s most important. His body is trying to re-learn his body.

“He’s really not a mechanics-driven guy, and hasn’t really thought too much about mechanics throughout his career. Just having things synced up with his delivery, he’s not quite there yet, and so he and (pitching coach Rick Honeycutt) are working through that.”

COVERING THE BASES

Rookie Caleb Ferguson will face the Giants in Sunday’s series finale, his third major-league start. He threw lasted only 1-2/3 innings in his debut and four in his second start, looking somewhat less jittery after his promotion June 6 from Triple-A Oklahoma City.

“He looks right,” Roberts said when asked if he expected a more relaxed showing Sunday from Ferguson. “I thought the first start he threw the ball well. He went deeper in his last start. I think in this third one is going to be even better.” …

Roberts said reliever Pedro Baez suffered from “a little tendinitis in the front of his (right) shoulder,” which was why the Dodgers placed him on the DL on Friday. “When a guy like that says there’s something not right in his shoulder, we’ve got to listen,” Roberts said. …

The Dodgers signed pitcher Drew Hutchison to a minor-league contract. He’s expected to make his debut Sunday with Oklahoma City after the Philadelphia Phillies designated him for assignment May 31. He has appeared in 92 games in the majors, mostly with the Toronto Blue Jays.